Type and watts of light

By
Ed Rosenthal
on December 22, 2003

I know you prefer HPS to MH lights but which would be better to use: a 400-watt HPS or a 1000-watt MH? The MH lumens are more than twice the HPS. Isn’t that the main concern? Price-wise they cost about the same. Which is best? Thanks!
Linda,
Internet

The purchase price is the smallest part of the total cost of a garden’s light. The biggest cost is running the light ? the electric bill.
A 400-watt lamp uses only 40% of the current that a 1000-watt lamp uses. However, a 1000-watt lamp will more than double a garden’s yield from what a 400-watt lamp can produce, when the plants are provided with adequate amounts of CO2 and nutrients.

The 400-watt and 1000-watt lamps are both good values depending on the size of the garden and the budget of the gardener. A 1000-watt lamp will require more electricity but will give a better yield. These factors are more important in the cost-benefit analysis.

Even if it is a little more costly to purchase, a 1000-watt HPS lamp would provide the best yield and be the best buy in the long run. The electricity use is the same as a 1000-watt MH, but the HPS produces much more light in the useable spectrum, increasing the garden’s efficiency by approximately 15%.

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